How do I install Cassiopeia?

Install the matching mod loader (Forge, Fabric or NeoForge) for your Minecraft version. Download the .jar. Put it in the .minecraft/mods folder and launch that loader profile. Opens on Modrinth — not every file is mirrored on our own servers.

What Minecraft version does Cassiopeia work with?

The listing gives Minecraft 1.21.10, 1.21.11. This is the version stated by the author or source site, not something we verified ourselves.

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Cassiopeia

by block_nate · on Modrinth

A simple mod that adds a chatbot to your Minecraft chat specifically for use to guide players in Hypixel Skyblock!

Which Minecraft do you have?

Every version of the game needs its own build. Pick yours, then download — the wrong build installs fine and then does nothing in the game. This mod is built for Fabric only.

Minecraft 1.21.10–1.21.11Newest
Minecraft 1.21.5–1.21.8

⬇ Download for 1.21.10–1.21.11 ⬇ Download for 1.21.5–1.21.8

I don't know my version or loader

Open the Minecraft launcher and look at the profile you play on — it names both, like fabric-loader-1.21.4. The version also shows in the bottom-right corner of the game's main menu.

No loader in the profile name? Then it's plain Minecraft, and these mods won't run — you need Fabric or NeoForge installed first.

Open in MC Java Mods Get it on Google Play →

Cassiopeia – Multi-AI Chat Integration for Minecraft

Cassiopeia is a client-side Fabric mod that integrates multiple AI models into the Minecraft chat system. Players can send prompts to their chosen AI directly in-game and receive real-time responses.

Features

Multi-AI Support: Choose between Gemini 2.5 Flash, GPT-5, Grok, and Claude 3 Sonnet.
Game State Integration: AI can see what item your holding and armour your wearing and more
Local Storage: API keys, prompts, and history are stored locally — never shared with anyone except your selected AI provider.
Conversation Memory: Remembers your last 5 exchanges for conversational consistency.

Usage

/ai

— Shows all available commands and usage info in-game.

/ai <prompt>

— Send a prompt to the currently configured AI model.

/ai api <model> <key>

— Save your API key for a model (Gemini, OpenAI, grok, Claude).

/ai model <name>

— Switch to a different AI model.

/ai clear

— Clear stored conversation history.

Get Your API Keys

Gemini API Key (Google) (free with a Google account)
OpenAI API Key (GPT-5)
xAI API Key (Grok)
Anthropic API Key (Claude 3)

Community

For support, suggestions, and early info on new updates, join our Discord server.

Quick facts

Edition: Minecraft Java
File type: .jar
Minecraft versions listed: 1.21.10, 1.21.11
How to install: Install the matching mod loader (Forge, Fabric or NeoForge) for your Minecraft version. → Download the .jar. → Put it in the .minecraft/mods folder and launch that loader profile.
Where to get it: Opens on Modrinth — not every file is mirrored on our own servers.

Install steps are the general flow for this file type — How to install Minecraft Java mods & modpacks walks through it step by step.

Verified by MCModsHub

Ships as cassiopeia-1.1.15.jar — drop this file into the mods folder
Download size: 79 KB
Download link checked 9 Sept 2026 — working

These come from our own check of the pack file, not from the source page.

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